What's the difference between kinds of Q235 steel plate

The quality grade of common carbon structural steel Q235 can be divided into A, B, C, D and E. The quality of A is poor and that of E is the highest. Different grades of Q235 steel plate have different characteristics, which are mainly different from the following aspects: impact temperature: Q235A does not require impact toughness test; grade Q235B is for room temperature (20℃); grade Q235C is for 0℃; grade Q235D is for - 20℃; grade Q235E is for - 40℃.

The chemical content of high-grade steel plate is different. We all know that the chemical content of steel plate determines the quality of steel plate; high quality carbon structural steel is carbon steel with carbon content less than 0.8%, which contains less sulfur, phosphorus and non-metallic inclusions than carbon structural steel, and has better mechanical properties. The Q235A steel plate contains C≤0.22%, Mn≤1.4%, Si≤0.35%, S≤0.050, P≤0.045, Q235B steel plate contains C≤0.20%, Mn≤1.4%, Si≤0.35%, S≤0.045, P≤0.045, Q235C steel plate contains C≤0.17%, Mn≤1.4%, Si≤0.35%, S≤0.040, P≤0.040, Q235D steel plate contains C≤0.17%, Mn≤1.4%, Si≤0.35%, S≤0.035, P≤0.035.